EVERYDAY SCIENCE

Detailed explanation-1: -The first stage is entry. Entry involves attachment, in which a virus particle encounters the host cell and attaches to the cell surface, penetration, in which a virus particle reaches the cytoplasm, and uncoating, in which the virus sheds its capsid.

Detailed explanation-2: -Most productive viral infections follow similar steps in the virus replication cycle: attachment, penetration, uncoating, replication, assembly, and release.

Detailed explanation-3: -The attachment phase of replication comprises specific binding of a virus-attachment protein (or ‘antireceptor’) to a cellular receptor molecule. Virus receptors on cell surfaces may be proteins (usually glycoproteins) or carbohydrate residues present on glycoproteins or glycolipids.

Detailed explanation-4: -Viruses attach to proteins known as cellular receptors or attachment factors on the surface of the host cell [11, 12]. In addition, certain membrane lipids and glycans may be necessary for viral entry. These factors stabilize the virus on the cell surface and allow it to circumvent the cell’s barriers to entry.